Weak private key generation in SSH.NET

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS

• CVE-2022-29245: 1.48% estimated exploitation activity in the next 30 days; percentile 73.92 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

During an X25519 key exchange, the client’s private is generated with System.Random: Source: KeyExchangeECCurve25519.cs Source commit: https://github.com/sshnet/SSH.NET/commit/b58a11c0da55da1f5bad46faad2e9b71b7cb35b3 System.Random is not a cryptographically secure random number generator, it must therefore not be used for cryptographic purposes. Impact When establishing an SSH connection to a remote host, during the X25519 key exchange, the private key is generated with a weak random number generator whose seed can be bruteforced. This allows an attacker able to eavesdrop the communications to decrypt them. Workarounds To ensure you're not affected by this vulnerability, you can disable support for curve25519-sha256 and curve25519-sha256@libssh.org key exchange algorithms by invoking the following method before a connection is established: Thanks This issue was initially reported by Siemens AG, Digital Industries, shortly followed by @yaumn-synacktiv.

Published by the source

1 Jun 2022, 19:50 UTC

Last modified by the source

27 Jan 2023, 05:03 UTC

Source last checked

26 Oct 2026, 16:58 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-72p8-v4hg-v45p

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# Patch Next advisory brief: CVE-2022-29245

Advisory: Weak private key generation in SSH.NET
IDs: CVE-2022-29245, GHSA-72p8-v4hg-v45p
Record: https://patchnext.com/advisories/cve-2022-29245 (revision 1, source checked 26 Oct 2026, 16:58 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: ssh.net 2020.0.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- NuGet ssh.net: affected < 2020.0.2; fixed in 2020.0.2

## Suggested inspection (read-only)
- NuGet ssh.net: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on ssh.net.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-72p8-v4hg-v45p (GitHub-reviewed advisory GHSA-72p8-v4hg-v45p lists affected ranges: NuGet ssh.net >=0 <2020.0.2)

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